Gear Travel/Movement in Assemblies

Hello, there. I'm in the middle of a project in Onshape, which is designing a quad-rotor Wankel rotary engine. I am currently working on the fixed gears that will be mounted at either end of the engine. I suppose I should note that the engine is to be 3D printed and run pneumatically. Back to the issue. I have modeled the rotor and its inner gear teeth as well as the gear that helps force the rotor to move in the correct path, though I have not modeled the plate for and bolt holes for bolting the gear to the housing. The problem/question I have is whether I am able to have a gear mate where one of the gears is fixed in place, and whether I would be able to animate this so I can be sure that it would mesh properly the whole way 'round. Any help is appreciated.